Chapter 15 Physical Science (vEnd of chapter work )

What are the differences between compounds and mixtures?

• Compounds have a fixed composition; mixtures do not.

• Mixtures have a fixed composition; compounds do not.

• Compounds can only be elements; mixtures cannot.

• Mixtures are pure substances; compounds are not.

How are elements and compounds defined?

• Elements are substances made of different types of atoms; compounds are not.

• Compounds are substances that can be broken down into elements; elements cannot.

• Elements are substances made of one type of atom; compounds consist of two or more elements combined.

• Compounds are made of one type of atom; elements are made of molecules.

How are suspensions, solutions, and colloids related?

• They are all types of elements.

• They are all types of compounds.

• They are all types of heterogeneous mixtures.

• They are all types of homogeneous mixtures.

What is a pure substance?

• A substance that can be separated into elements or compounds.

• A substance that is a mixture of elements and compounds.

• A substance with a fixed composition.

• A substance that is always a liquid.

Which of the following is an example of an element?

• Water

• Salt

• Helium

• Air

What is titanium used for?

• Making window glass

• Running computers

• Bone or joint replacements and aircraft construction

• Making plants green

Where is silicon commonly found?

• In smoke detectors

• In chlorophyll

• In sand as silicon dioxide

• In jet engines

What does magnesium contribute to in plants?

Why are lead aprons used during X-ray exposure?

• Because they are lightweight and strong

• To protect the rest of the body from X-ray exposure

• To keep the patient warm

• Because they are bendable and resistant to corrosion

What is a compound?

• A mixture of two or more elements that can be separated by physical means

• A single element that is used in construction

• A substance in which the atoms of two or more elements are combined in a fixed proportion

• A type of element that is bendable and resistant to corrosion